Installation of the Bosses [IAE]

TASK 72-50-50-400-801-A
Installation of the Bosses

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 400

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 95 and 85 lbf.in (1.07 and 0.96 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.V10-077A)	Approved Engine Oil

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [1000EM1] (ENGINE-1)
437AL, 438AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 71-13-00-410-010-A	Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 78-11-11-000-010-A	Removal of the Common Nozzle Assembly
TASK 78-11-11-400-010-A	Installation of the Common Nozzle Assembly (CNA)
TASK 78-11-12-000-010-A	Removal of the Engine Exhaust Cone
TASK 78-11-12-400-010-A	Installation of the Engine Exhaust Cone
TASK 78-30-00-040-012-A	Deactivation of the Thrust Reverser Hydraulic Control Unit (HCU) for Ground Maintenance
TASK 78-30-00-440-012-A	Re-activation of the Thrust Reverser Hydraulic Control Unit (HCU) after Ground Maintenance
Bosses

3. Job Set-up
Subtask 72-50-50-860-050-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) On the center pedestal, on ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE is in position.

Subtask 72-50-50-010-064-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Make sure that the fan cowl doors are open: (Ref. AMM TASK 71-13-00-010-010)
(a) FOR [1000EM1] (ENGINE-1)
437AL, 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL, 448AR.

Subtask 72-50-50-040-053-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser

WARNING: MAKE SURE THAT THE THRUST REVERSER HYDRAULIC CONTROL UNIT (HCU) IS DEACTIVATED BEFORE YOU DO WORK ON OR AROUND THE THRUST REVERSER. IF THE HCU IS NOT DEACTIVATED, THERE IS A RISK OF UNWANTED THRUST REVERSER OPERATION WHICH CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

(1) Make sure that the thrust reverser is unserviceable (Ref. AMM TASK 78-30-00-040-012).

Subtask 72-50-50-010-065-A ** ON A/C NOT FOR ALL

D. Make sure that the common nozzle assembly is removed (Ref. AMM TASK 78-11-11-000-010).

Subtask 72-50-50-010-066-A ** ON A/C NOT FOR ALL

E. Make sure that the exhaust cone is removed (Ref. AMM TASK 78-11-12-000-010).

4. Procedure
Subtask 72-50-50-420-060-A ** ON A/C NOT FOR ALL

A. Installation of the Bosses
(1) Put the boss (5) in position between mounting flanges on the turbine exhaust case.
(2) Install the pins (4).
(3) Apply an Approved Engine Oil (Material No.V10-077A) to the threads of the bolts (1).
(4) Install the stop (3) to the boss (5) with the bolts (1) and the nuts (2).
(5) TORQUE the bolts (1) to between 95 and 85 lbf.in (1.07 and 0.96 m.daN )

.
(6) Do the steps above for the remaining boss.

5. Close-up
Subtask 72-50-50-942-058-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Install the exhaust cone (Ref. AMM TASK 78-11-12-400-010).

Subtask 72-50-50-942-059-A ** ON A/C NOT FOR ALL

B. Install the common nozzle assembly (Ref. AMM TASK 78-11-11-400-010).

Subtask 72-50-50-942-060-A ** ON A/C NOT FOR ALL

C. Activation of the Thrust Reverser
(1) Do the activation of the thrust reverser HCU (Ref. AMM TASK 78-30-00-440-012).

Subtask 72-50-50-942-061-A ** ON A/C NOT FOR ALL

D. Close Access
(1) Close the fan cowls (Ref. AMM TASK 71-13-00-410-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Remove the WARNING NOTICE(S).
(3) Remove the access platform(s).

[Rev.10 from 2021] 2026.04.01 02:46:31 UTC